Billy tells his sister Sarah that he is twice as old and twice as smart as her right now. Sarah says that in five years should be twice as old as she is now and that Billy won’t be. How old will they be in five years?

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How do you find principle and simple interest

How many sides does a regular polygon have if each exterior angle measure is 45 degrees explain your answer, i really don't understand this.

At the "no mutants allowed" country farm, every sheep has 4 legs, every chicken has two legs, and all animals have only 1 head. asked to count how many sheep and chicken are in the fields, a farm boy reports back that there are 140 feet and 50 heads. how many sheep and chicken are there? there are sheep and chicken at the farm.